Transactions. Section on Ophthalmology. American Academy of Ophthalmology and Otolaryngology最新文献

Fifteen patients with meningiomas arising from the optic nerve sheath within the orbit occurred in a large series of patients with orbital tumors. Eleven patients were women; there was only one child. Thirteen patients had a similar clinical appearance. In each case visual loss was the first symptom. Proptosis, which occurred in only ten patients, developed later (the time interval was three months to five years). Optic disc edema or atrophy was present in all 15 patients, some of whom had optociliary shunt vessels on the optic disc. The new fine-matrix EMI scanner (320x320) demonstrated the tumors but even clearer pictures of the lesion could be obtained using a c-mode ultrasonic scanner. The treatment of these meningiomas is essentially surgical.

Midfacial trauma can produce fractures and soft tissue injuries and can embed foreign bodies within the eye, orbit, and brain. A careful history and ocular examination are fundamental to the evaluation of any patient who has suffered orbital injuries. Damage to the paranasal sinuses and the nasolacrimal system should be considered as a possible consequence of trauma to the orbit. Fractures are best evaluated by conventional roentgenograms with linear or hypocycloidal tomography. Bony fragments can be well visualized by xeroradiography. Positive contrast orbitography may be hazardous and has been replaced by noninvasive diagnostic techniques. Computerized tomography is useful in localizing soft tissue injuries and foreign bodies. Damage within the eye may be evaluated by ultrasonography. Cerebrospinal fluid leaks can be diagnosed by radionuclide cisternography, using nasal sample counting or scintiphotographic imaging. Carotid-cavernous sinus fistulas and other vascular abnormalities may be investigated by radionuclide angiography at minimal risk to the patient.

Neovascularization of the retina occurs in several types of sickle cell hemoglobinopathies and is highly characteristic in appearance. It arises in the equatorial plane of the fundus following preliminary arteriolar occlusions and arteriolar-venular anastomoses. Neovascular sea fans arise at the interface of perfused and nonperfused portions of the retina, starting during the first decade of life and continuing for many years thereafter. Although some sea fans undergo spontaneous autoinfarction, most show progressive growth and constant intravitreal transudation of plasma components. Traction on the sea fans and the retina results in bleeding into the vitreous, retinal tears, and retinal detachment. Therapeutic intervention with a variety of coagulative techniques is feasible and is usually indicated whenever sea fans are discovered. All therapeutic modalities are capable of inducing significant complications. This is particularly true of argon laser photocoagulation when energy is concentrated into small areas (less than 200 mu) for short durations (less than 0.2 second). With appropriate precautions, photocoagulation results in a high rate of successful obliteration of neovascular tissue. Both vitrectomy and scleral buckling are valuable therapeutic procedures, but both have disproportionately high complication rates in eyes with the propensity for intravascular sickling of erythrocytes. Specific prophylactic measures are therefore indicated when these operative techniques are employed in patients with sickle cell diseases.

Optociliary veins occur in three clinical settings: in chronic central retinal vein obstruction, with retro-orbital tumors, and as congenital anomalies. In the last setting, associated anomalies of the disc and retinal vessels may be present, which makes differentiation from the first two difficult. Fluorescein angiography may be of value in making this differentiation for, in some if not all congenital OC veins, the direction of flow is from the choroid into the central retinal vein. Two cases are presented in which a congenital optociliary vein was present in association with a fundus picture mimicking a central retinal vein obstruction or papilledema. In both cases, fluorescein angiography demonstrated that the vessel was a congenital anomaly, draining from the choroid into the retina.